בדיקות והתערבות בהריון בעקבות פגם גנטי

Thank you in advance for your help with this issue. Right now, all of this is hypothetical… but I am trying to gather advice since I hope to be married someday soon and start a family, G-d willing.
I have a sister who was born with a severe genetic disorder called 5p- syndrome, also called Cri du Chat. Like my mother and my other sister, I have what has been called "mosaic" chromosomes.
So we don't have the disorder ourselves, but we can pass it on to our children (the mosaic spontaneously appeared in my mother).
I have talked to Dr. Joan Overhauser, a geneticist who is a specialist in this disorder and knows the karyotype of my family. The situation is that, statistically, I have a 50% chance of having a child affected by the syndrome. However, in reality, many of the affected fetuses (but not all), would spontaneously abort, leaving about a 15% chance that I would carry to term a child with the syndrome.
The geneticist advised me that the following options are available to me, from a purely medical point of view (she knows that I am orthodox and has advised me to speak with a Rabbi about this issue): -CVS sampling, which she mentioned is done at about 10-11 weeks, to test for the abnormality using a new technique called FISH, and then possible termination of the pregnancy. She says it would be very easy to determine the chromosome make-up of the fetus since they would know exactly what to look for already. -amniocentesis testing done at a later time, and then possible termination of the pregnancy -in-vitro fertilization followed by blastocyst testing, with implantation of normal embryos (very involved and expensive procedure but has been used for such purposes) -no intervention My question is, what is the best way to cope with this situation from a halachic standpoint? Also, if in-vitro fertilization and blastocyst testing were permitted, but the procedure was too expensive (estimated at $10,000 to $20,000 here in the U.S.), would there be other options?
Thank you.
It is difficult to convey how much I appreciate your attention to this question.
In the meantime, I looked up early CVS on the internet and saw warnings associated with the procedure — possible deformities, G-d Forbid, caused to the limbs of the embryo. I will try to find out whether the genetic test I would need could be performed at 7 weeks. I am guessing that Rabbi Halperin might say the whole testing procedure and possible termination would have to be completed before the embryo was 40 days old. I am also interested in finding out more about what would be involved with the IVF/blastocyst testing. i.e., is it permitted, and how would it affect a couple trying to have children? Is it considered the preferred route, halachically? Thank you again, very much,